Aircraft of a certain size are generally fitted with a braking computer which, in order to achieve a given amount of deceleration, generates a braking force objective in response either to the pilot pressing on the brake pedals, or in response to the pilot setting a determined level of deceleration (the “autobrake” function). In practice, this braking force objective is implemented by sending braking setpoints to power driver members associated with the brakes, the setpoints being identical for all of the brakes and being such that the sum of the braking forces developed by the brakes in response thereto achieves the braking force objective. This overall braking force is applied by the braking computer for a period of time that is sufficiently long to enable the brakes to dissipate in friction the energy that is needed for achieving the required deceleration of the aircraft.
While taxiing on the ground, i.e. while the aircraft is moving at low speed on an airport, methods are known for distributing braking in which braking is applied using only a fraction of the brakes. Then, next time the brakes are applied, braking is performed with the complementary fraction of the brakes. The purpose of that method is to reduce overall wear of the brake friction elements.
Nevertheless, that type of distribution presents certain drawbacks. The subdivision of the brakes into two complementary brake fractions is determined a priori, and in general, each fraction comprises half of the brakes selected in such a manner that braking with identical braking forces on each active brake gives rise to braking that is symmetrical. Thus, although the brakes suffer less wear overall, it can happen that the friction elements of one of the brakes heat up faster than in neighboring brakes and nevertheless reach a temperature range in which friction element wear is faster.
Anti-slip protection schemes are also known that consist in momentarily reducing the braking force of a brake if the corresponding wheel begins to slip. These corrections are applied to one wheel or another without any overall distribution strategy being implemented. Momentarily, the total braking force can drop below the braking objective.
Document GB 1 585 321 discloses a method of equalizing the energy dissipated between two brakes by calculating, for each brake, a rate of energy dissipation by multiplying the torque generated by the brake by the criterion of wheel rotation, and then integrating that rate. That method does no more than distribute, a posteriori, the braking forces between the two brakes on the basis of the amount of energy that has been dissipated by each of those brakes.